Ideas: 24th month free or reducing rent?

[Dan Griffin]

My wife and I are looking for someone to stay 2 years in our own personal residence while we are out of state. I was trying to figure out a positive incentive to get one tenant to stay the entire 2 years. What do you guys think about a lease that said the 24th month is free. Is that crazy?
My wife says the incentive is too far away, and people wouldn't "feel" it.

Perhaps a decreasing rent? (For example, every 6 months, the rent goes down $50.) I know that when Boost Mobile had the plan that reduced your cell phone bill the longer you stayed, it certainly kept me around.

What do you folks think? Ever tried something like this?

Dan